Tobramycin in Serum or Plasma (Mass Concentration)

Why This Test Is Done

Your healthcare provider may order this test if you’re receiving tobramycin, a strong antibiotic used to treat serious bacterial infections like pneumonia, sepsis, or infections in the bloodstream, lungs, or bones. It helps track how much of the drug is in your blood to prevent toxic levels that could harm your kidneys or nerves.

What to Expect Before the Test

No special preparation is needed. A blood sample is drawn from a vein, usually in your arm, by a healthcare professional. The process is quick and typically painless, though you might feel a slight pinch. You can resume normal activities immediately afterward.

What the Test Results Mean

Results are compared to a reference range specific to tobramycin, which varies based on your weight, kidney function, and how you’re being treated. High levels may indicate too much drug in your system, while low levels could mean the infection isn’t fully responding to treatment.

Potential Side Effects or Risks

Tobramycin can cause side effects like nausea, vomiting, or kidney damage if levels are too high. Your provider will adjust your dose if needed based on these results. Rarely, it may affect your nerves or hearing.